RT8278 RICHTEK [Richtek Technology Corporation], RT8278 Datasheet - Page 7

• Manufacturer Part Number: RT8278
• Description: 2A, 24V, 3MHz Step-Down Converter
• Manufacturer: RICHTEK [Richtek Technology Corporation]

DS8278-02 March 2011
(100mV/Div)
V
(1A/Div)
OUT
I
OUT
2.4
2.3
2.2
2.1
2.0
1.9
1.8
4.3
3.9
3.5
3.1
2.7
2.3
1.9
1.5
-50
0
Switching Frequency vs. Temperature
f
V
l
SW
OUT
IN
= 400kHz
= 12V, V
= 0 to 2A, f
-25
Current Limit vs. Duty Cycle
Load Transient Response
20
f
SW
OUT
0
= 2.2MHz
SW
Time (100μs/Div)
Temperature (°C)
= 3.3V
Duty Cycle (%)
= 2.2MHz
40
25
V
l
OUT
50
IN
60
= 12V, V
= 0.3A, R
75
OUT
80
RT
100
= 3.3V,
= 24kΩ
100
125
(10mV/Div)
(100mV/Div)
(10V/Div)
V
(1A/Div)
V
(1A/Div)
V
OUT
OUT
I
SW
OUT
I
4.5
4.0
3.5
3.0
2.5
2.0
1.5
L
-50
-25
Current Limit vs. Temperature
Load Transient Response
Output Ripple Voltage
V
IN =
0
Time (200ns/Div)
Time (100μs/Div)
Temperature (°C)
12V, V
25
V
I
OUT
IN
OUT =
= 12V, V
V
I
= 1A to 2A, f
OUT
IN
V
I
OUT
50
IN
= 12V, V
= 1 to 2A, f
3.3V,
= 12V, V
= 2A, f
RT8278
www.richtek.com
OUT
75
f
SW
OUT
= 3.3V
SW
SW
OUT
= 2.2MHz
S
= 2.2MHz
= 2.2MHz
= 3.3V
= 2.2MHz
100
= 3.3V
125
7